Biomedical Engineering Reference
In-Depth Information
C .0g potassium-sodium tartrate (Seignette salt) in 100 ml
ddH
2
O
Dmix1vol.Band1vol.C,andthenadd50vol.A
E Folin-Ciocalteu's phenol reagent (stock), 1 + 1 diluted with
ddH
2
O (Tables 1.4, 1.5)
Standard
2.0 mg/ml BSA in 0.1 N NaOH (stable at 2 - 8
◦
C for sev-
eral months)
Dilute the sample with sodium hydroxide to a final concentra-
tion of about 0.1 moles NaOH/l and to an amount of protein within
the measuring range.
µ
Table 1.4.
Dilution protocol of the microassay (0-40
g; F
OLIN
method)
Standard
0.1 N NaOH
Protein per assay
µ
µ
µ
µ
/
(
l)
(
l)
(
g)
(
g
ml)
0
100
0
0
10
90
5
200
20
80
10
400
30
70
15
600
40
60
20
800
50
50
25
1000
60
40
30
1200
80
20
40
1600
Table 1.5.
Protocol of micromethod (F
OLIN
method)
µ
Sample and standard, respectively
25
l
µ
Soln. D
250
l
Mix on a shaker for 5 - 10 min at RT
µ
Soln. E
25
l
Mix on a shaker for 30 - 45 min at RT
MeasurewithanEIAreader
at 620 nm
1.1.1.4 Protein Determination in the Presence
of Interfering Substances
If a sample contains a larger amount of interfering substances, i.e.,
the blank gives a high value, these substances may be removed
according to this protocol. But some detergents, such as digitonine,
prevent the precipitation of the proteins.
A
0.15% sodium deoxycholate (w/v) in ddH
2
O
Solutions/Reagents
B 72% trichloroacetic acid (w/v) in ddH
2
O
C1%
SO
4
(w/v) in ddH
2
O
D
2% sodium-potassium tartrate (w/v) in ddH
2
O
E
3.4% sodium carbonate (anhydrous) (w/v) in 0.2 N NaOH
